<ul id="maintab" class="shadetabs">
    <li class="selected" onclick="switchTab('User/WP_User.php?action=2','content_area',this);">&nbsp;&nbsp;Usuarios&nbsp;&nbsp;</li>
    <li onclick="switchTab('User/WP_User.php?action=5','content_area',this);">&nbsp;&nbsp;Nuevo Usuario&nbsp;&nbsp;</li>
</ul>
<div id="content_area" class="contentstyle">
    {include file="User/user_main_cont.tpl"}
</div>